package cn.pku.sirx.snad.uias.dao;

import java.util.Date;

import cn.pku.sirx.snad.ad.dao.IDao;
import cn.pku.sirx.snad.uias.model.entity.MessageInfluence;

/**
 * @author WangXiao
 */
public interface IMessageInfluenceDao extends IDao<MessageInfluence> {

	/**
	 * Get the message board influence from a user to another, in a given
	 * period.
	 * 
	 * @param fromUserId
	 *            a user ID, null means no limit on the influencer
	 * @param toUserId
	 *            another user ID, null means no limit on the influencee
	 * @param fromDate
	 *            the begging of the period (included), null means no limit
	 * @param toDate
	 *            the end of the period (included), null means no limit
	 * @return message board influence from a user to another, in a given period
	 */
	double getInfluence(String fromUserId, String toUserId, Date fromDate,
			Date toDate);

}
